Holter Monitor in Dogs

What is a Holter monitor?

A Holter monitor is a portable device used to continuously monitor the electrical activity of the heart. Its extended recording period is useful for observing occasional or intermittent cardiac arrhythmias that may be difficult or impossible to identify during a routine clinical examination. Holter monitors are commonly used in boxer dogs and doberman pinschers to diagnose specific forms of heart disease and abnormal heart rhythms. 

What does a Holter monitor do?

The monitor is usually worn for at least 24 hours during normal activity. You should keep a diary of what activities your dog does while wearing the monitor, such as taking a walk, eating, sleeping, or playing. There is a button on the monitor for you to press to mark an observed event such as an episode of weakness. After the recommended time, you will return the monitor and diary to your veterinarian's office. Your veterinarian will analyze the recorded ECG, looking for abnormalities.  Alternatively, your veterinarian may submit the recording to a cardiology telemedicine service for analysis. 

Why does my dog need to wear a Holter monitor?

A Holter monitor is typically used for patients with a history of syncope (fainting) or if your veterinarian detected abnormal or irregular heartbeats during a clinical examination of your dog. Some of the uses include:

• determine heart rate variability during normal activity, exercise, rest, or sleep
• diagnose the type of arrhythmia (abnormal or irregular heartbeat or rhythm) to determine the correct treatment
• analyze the effectiveness of prescribed cardiac drugs
• evaluate pacemaker function

How does my dog wear a Holter monitor?

The Holter monitor used for dogs consists of a special vest, which contains the monitor, attached to several ECG lead wires. It is unobtrusive and most dogs ignore its presence very quickly. Your dog will likely have several areas of fur shaved to attach the ECG leads to the skin.

If your dog requires a Holter monitor, your veterinarian will give you specific instructions on its use. This relatively simple but highly effective device has saved countless human and animal lives since it was first introduced almost 70 years ago.